<div><p>Nitrenes are reactive
intermediates that are known to generate high interest organic molecules. Due
to their inherent instability, nitrenes are often stabilized by introducing them
to transition metal complexes. Many transition metal stabilized nitrenes (M=NR<sub>2</sub>)
have been reported and some of these complexes have been shown to control nitrene
reactivity and selectivity. Transition metal nitrene reactivity can be
categorized into two main groups: bond-insertion and group transfer reactions.
In the reference to the former, chapter one of this dissertation highlights
using unique dinuclear Ni<sub> </sub>catalysts to generate nitrenes from
aromatic azides. These Ni<sub>2</sub> nitrenes are used towards selective C(sp<sup>2</sup>)−H
bond amination in order to
generate indole and carbazole derivatives. This work highlights the unique
properties of the Ni<sub>2</sub> imide that enable a 1,2-addition
pathway, which contrasts
known bimetallic nitrene insertion reactions. A detailed mechanistic study,
primarily using density functional theory (DFT) is the focus of this chapter.</p>
<p>Chapter two of this dissertation focuses on nitrene group
transfer. In particular, this chapter highlights the ability of the dinuclear
Ni<sub> </sub>catalyst [<i><sup>i</sup></i><sup>-Pr</sup>NDI]Ni<sub>2</sub>(C<sub>6</sub>H<sub>6</sub>)
to react with aromatic azides to perform N=N coupling. A large scope of functional
groups are tolerated in high yield with short reaction times. Catalyst
comparison studies, studies on relevant catalytic intermediates for N=N
coupling and reaction kinetics are shown in this chapter. Lastly, chapter three
showcases the expansion of the nitrene group transfer ability of [<i><sup>i</sup></i><sup>-Pr</sup>NDI]Ni<sub>2</sub>(C<sub>6</sub>H<sub>6</sub>) to generate high
molecular weight azopolymers from aromatic diazides. These azopolymers are
generated from monomers often used in organic semi-conducting materials. End
group control and post polymer functionalization are highlighted in this
chapter. Lastly, this work showcases a new polymer, polyazoisoindigo, as the
first organic semiconducting material that reversibly transitions from a colored
to colorless state upon reduction.</p><br></div>
| Identifer | oai:union.ndltd.org:purdue.edu/oai:figshare.com:article/15044229 |
| Date | 23 July 2021 |
| Creators | John M Andjaba (11155014) |
| Source Sets | Purdue University |
| Detected Language | English |
| Type | Text, Thesis |
| Rights | CC BY 4.0 |
| Relation | https://figshare.com/articles/thesis/Catalytic_Nitrene_Reactions_Enabled_By_Dinuclear_Nickel_Catalysts/15044229 |
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